reproduce (this is a W=1 build): # https://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm.git/commit/?id=85de428c7ca1b71457690b95e162662d0edb2792 git remote add akpm-mm https://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm.git git fetch --no-tags akpm-mm mm-new git checkout 85de428c7ca1b71457690b95e162662d0edb2792 git clone https://github.com/intel/lkp-tests.git ~/lkp-tests # apt-get install sparse # sparse version: v0.6.4-71-g610d841d # save the config file mkdir build_dir && cp config build_dir/.config COMPILER_INSTALL_PATH=$HOME/0day COMPILER=gcc-12.5.0 ~/lkp-tests/kbuild/make.cross W=1 C=1 CF='-fdiagnostic-prefix -D__CHECK_ENDIAN__ -fmax-errors=unlimited -fmax-warnings=unlimited' O=build_dir ARCH=s390 olddefconfig COMPILER_INSTALL_PATH=$HOME/0day COMPILER=gcc-12.5.0 ~/lkp-tests/kbuild/make.cross W=1 C=1 CF='-fdiagnostic-prefix -D__CHECK_ENDIAN__ -fmax-errors=unlimited -fmax-warnings=unlimited' O=build_dir ARCH=s390 SHELL=/bin/bash